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Blender 2.61 Release Notes

Motion tracking support has been added, to reconstruct camera and object animation from real footage, and composite 3d rendered object into movie clips.

A new Movie Clip editor for loading clips, tracking points and reconstructing motion was added. Constraints can apply this reconstructed motion into the scene, and compositing nodes are available for (un)distorting rendered animations or real footage.

Cycles is a new render engine that is available next to Blender Internal. It is a raytracing based render engine with support for interactive rendering, a new shading node system, new texture workflow and GPU acceleration.

It is still in development, and more production features are planned to be added, this is the first preview release.

Dynamic paint is a new modifier and physics system that can turn objects into paint canvases and brushes, creating vertex colors, image sequences or displacement.

This makes many effects possible that were previously difficult to achieve, for example footsteps in the snow, raindrops that make the ground wet, paint that sticks to walls, or objects that gradually freeze.

The render engine API has been extended for closer integration, a mechanism to detect changes in scenes and persistent callbacks were added, the noise module was updated, and easier access to library datablocks was added, along with various other changes.